Refrigerating apparatus



3 Sheets-Sheet 1.

(No Model.)

0. 0. PALMER. REFRIGERATING APPARATUS.

No. 290,794. Patented Dec. 25, 1883.-

INVENTOR xy td 2 t e e h t e e h S 3 I R E M L A P O C (No Model.)

. REFRIGERATING APPARATUS. A No. 290,794. Patented De0.Z5, 1888.

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N PEIERS F'Mln-Lvlhoguphu (No Model.) I a Sheets-Sheet 3.

C. G. PALMER. REFRIGBRATING APYARATUS.

Patented Dec. 25, 1883.

l'NVENTUR WITNESS W2 6L.

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REFRlGERATING APPARATUS.

SPEGIFIGATION forming part of Letters Patent No. 290,794, dated December25, 1883,

Application filed December 30, 1882. (No model.) Patented in EnglandApril 29, 1880, No. 1,752; in France April :29, 1880,

No. 136,416; in Victoria May 13, 1880, No. 2 828, and in New South WalesJune 30, 1880, No. 3,960.

To all whom it may concern..-

Be it known that I, CA ssIUs CLAY PALME of Oakland, Alameda county, inthe State of California, have invented a new and useful Improvement inRefrigerating Apparatus, of which the following is a specification.

Heretofore various methods for refrigerating air have been in use, withmore or less success, most prominent among which may be mentionedapparatus for circulating the air in direct contact with ice; also,apparatus for circulating the air in contact with the exterior ofvessels or pipes containing a freezing-min ture or brine; also,apparatus for compressing the air. cooling it in the compressed state,and expanding it; also, apparatus for circulating the air in contactwith the exterior of receptacles containing expanded ammonia-gas. All ofthese methods, however, are open to serious objections which are veryfamiliar to those acquainted with their use.

My improvement consists, primarily, in re frigerating air by the agencyof chloride of ethyl, which I have found to possess substantialadvantages, hereinafter referred to, over any of the refrigeratingagents which have heretofore been employed for the purpose.

My improvement also consists in the construction of certain apparatus bythe operation of which great advantages are acquired in the manipulationof a volatile fluid as an agent for the refrigeration of the atmosphere.

My improvement may be applied to the refrigeration of air for anypurpose, such as the preservation of putrescible substances; but I haveascertained that it has especial features of utility when employed forthe refrigeration of the air contained within compartments within whichbeer is placed for storage or fermentation.

Figure 1 of the accompanying drawings represents an elevation of a formof apparatus which I prefer to use in practicing my invention. Fig. 2represents a plan view. Figs.

3 and 4 represent detailed views of the refrigresented in both itsopened and closed positions in Fig. 4. My apparatus may be divided intofive partsnamely, th e refrigerator, the condenser, the compressor, thepressure-blower, and the chill-room.

The refrigerator may consist of any number of parts like that which I amabout to describe, the number of such parts being regulated inaccordance with the space required to be cooled by the apparatus. InFigs. 1 and 2 I have shown the refrigerator as containing four of theseparts. Figs. 3 and 4 show the construction of each of these parts.

A represents a cylinder, which I prefer to construct of copper whenchloride of ethyl is used as the refrigerating agent. This cylinder ismade sufficiently strong to withstand the atmospheric pressure upon itsexterior when in use, and is provided at each of its ends with a cap, aa, joined to the cylinder in such a way as to prevent the escape of theair, which is forced through the apparatus by the pressure-blower. Thesecaps I also prefer to construct of copper. Each of these caps isprovided (preferably at its center) with a pipe, b b, one for conductingair into the cylinder and the other for conducting it out.

Two perforated plates, 0 c, are situated within the cylinder-one at eachendand in such position that an air-space is left between eachperforated plate and the cap inclosing it. These perforated plates areso connected at their edge with the interior of the cylinder as toprevent any communication between the air which is contained within thecaps a a and the fluid which is contained between the perforated plates.From one of these perforated plates to the other extend tubes d, whichare fitted at each end into the perforations of the plates by tightjoints, which tubes afford communication from the air-space at one endof the cylinder to the air-space at the other end of the cylinder.plates are also made, preferably, of copper when chloride of ethyl isused. The pipe 0 serves to conduct the fluid into the space around thetubes in the cylinder, this pipe being preferably located at the top andnear one end of the cylinder. Another pipe, f, serves to conduct thefluid in its expanded state away from the cylinder, and is situated,preferably,

These tubes and the perforated ge.

near the other end of the cylinder, at its top, the second pipe beingsomewhat larger than the first pipe, so as to provide for the difference in volume of the fluid caused by its expansion in the cylinder. Thenozzle of the pipe Z), which conducts the air away from the cylinder, ismade, preferably, smaller than the pipe I), which conducts the air tothe cylinder, so as to assist the pressure-blower in keeping up acertain amount of pressure of air within the tubes din the cylinder, andthereby causing the air within the tubes throughout their whole lengthto be kept in intimate contact with the interior of the tubes. Thecylinders A are each surrounded by a masonry inclosure, which is sobuilt as to leave the caps to a projecting outside, and so as to leave aspace around outside each cylinder A on all sides. This space is dividedby a longitudinal partition, h, (shown in dotted lines, Fig. 1,)connecting the bottom of the cylinder with the floor; and the air whichis to pass through the refrigerator be fore entering the pipe I) isconducted by the pipe 1' into the inclosed space around the cylinder Aon one side of the partition 71, and passes around the cylinder to enterthe pipe 12, which connects with the inclosed space on the other side ofthe partition h, as shown. The object of thus conducting the air takenfrom the chill-room around the exterior of the cylinder before it ispassed through the tubes (1 is for economy, because the air receivedfrom the chill-room is colder than atmospheric air, and thus presents abarrier to the entrance of heat from the atmosphere into therefrigerator. Another object is to cause the air to leave considerableof its moisture condensed 011 the cold exterior of the cylinder A beforeit enters the tubes (1.

As means of access to the interior of the pipes d, the caps a a arepreferably each constructed in two equal parts, a a, Fig. 4c,

. said parts being hinged at s, and when closed meeting together, so asto make atight joint around the pipes b b and with each other. Whenclosed, they may be secured together by bolts or in any other suitablemanner. Each of the pipes f connects with the cylinder or pipe f,whichis in turn connected with the compressor by the pipe j. The pipe f ispreferably somewhat larger in area than the combined area of all thepipes f, for the purpose of distributing the suction of the compressorequally to all the cylinders and preventing the beats or strokes of thecompressor being felt in the cylinder A. The compressor is representedin Figs. 1 and 2, the compression-cylinder being lettered B and thesteam-cylinder O. No detailed description of this compressor isnecessary, since it is constructed similar to pumps for compressinggases, which have been heretofore in use.

The compression of the chloride of ethyl requires a power of only aboutfifteen pounds.

compression-pump through the exhaust-pipes f, f, and j, and from thecompressing-pump the fluid, in a compressed state, is conducted throughthe pipe to the condenser, where it is converted from a gas to a liquid.

The condenser consists of a tank, D, to contain a cooling-liquid,(generally water of ordinary temperature,) within which are immersed thecoil of pipes Z, through which the referigerating-fluid passes afterleaving the compressing-pump. for the purpose of having its temperaturereduced and being converted from the gaseous to the liquid statepreparatory to being returned to the refrigerator through the pipe m. Ofcourse, the condenser may be varied in many ways, and the cooling agentby which the condenser-pipes are sur rounded may be varied in many ways,in accordance with the amount of cold which it is desired to secure. 7 V

The chill-room may be a beer-cellar in a brewery, or it may be thechamber of a provision-refrigerator. It is constructed, preferably,withnon-condueting walls E, and contains a system of distributing-pipes, a,connected with the air-pipes b, containing openings 0, arranged atvarious points in the chill-room, so that the cold air may be equablydistributed to all parts of the chill-room, or wherever required. In thedrawings these openings are shown as located between the rows ofbeer-barrels 1), about on a level with their tops, though of course itmight be discharged at other points, if required. qisthepipethroughwhich the air is drawn out of the chill-room, which may beconnected with distributing-openings,

as shown.

In the fermentingroom of a brewery when cooled by my apparatus, the opentubs offermenting beer are stood in the positions occupied by thebarrels p in the drawings, and the cold air, being thus discharged fromthe openings o in the position shown, meets with and absorbs thecarbonic-acid gas flowing over the edges of the tubs; but at the sametime the draft of air is so directed by the nozzles 0 as to produce thelowest temperature at the bottoms of the tubs, whereby the beer atthebottoms of the tubs is kept as cold as or colder than the beer at thesurface, so that the gas which is thrown off by the fermentation of thebeer at the bottom of the tubs will not be reabsorbed by the beer abovein passing through it.

The pressure-blower F is constructed like the pressure-blowersheretofore in usesuch as the Baker or Root blowersand hence need not bespecifically described. It is driven by a belt or other means ofconnection with the engine. It draws the air from the chillroom throughthe pipe (1 and forces it into the refrigerator through the pipes o'-and 2'. Of course other air-forcing apparatus might be used in lieu ofthe pressure-blower, though I think not to so great an advantage. Theconnections of the pressure-blower might be IIO reversed, so as todischarge the cold air from the pipe (1 and exhaust it through the pipesn n and openings 0.

By arranging valves in the pipes z and b and e and f connected with eachof the cylinders A, I can throw any one or more of the cylinders into orout of operation at will, so

. that any one of them canbe cleaned or repaired while the others are inoperation, both the refrigerating-fluid and the air being diverted fromentering the cylinder for the time being.

The number and length of the tubes and the frequency of compression andexpansion of the refrigerating-fluid for securing the proper degree ofcold will of course depend upon the size of the chill-room and theinfluence of external heat and the amount of heat given off by thecontents of the chill-room; but for a chill-room having ten thousandcubic feet capacity, with ordinary non-conducting walls, and containingbarrels of fermenting beer, I havefoundthatatemperature of38Fahrenheitcould be secured by refrigerators containing eightyfour tubes, eachtubeone and one-f0 urth inch in diameter and seven feet long, thecylinder being thirty inches in diameter, and the amount of chloride ofethyl in use being about eight hundred pounds, and being compressed andexpanded about once in every two or three hours, the condenser alsocontaining water at about 76 Fahrenheit temperature, and the air in thechill-room being conducted through the cooling-tubes about once everyhour.

In operating my apparatus I prefer to have at least one of the cylindersA all the time idle while the others are in operation, so that if any ofthose in operation require cleaning or repairs its valves can be closed,and the valves of the idle cylinder can be opened, so that the number ofcylinders in operation will not be reduced. In operating the apparatusshown in Figs. 1 and 2, therefore, I open the valves of three of thecylinders, leaving the valves of the fourth one closed. I then start theoperation of the pressure-blower and the compressing-pump. Beforeintroducing the chloride of ethyl into the apparatus, the valve is, Fig.1, is closed and a pet-cock, k, is opened. so that by operating thecompression-pump the air is exhausted from all parts of the apparatusintended for the volatile fluid. The chloride of ethy1,which underatmospheric pressure is in the form of a 'liquid, is then allowed toflow into the apparatus through the petcock a, and, expanding, fills theapparatus with its vapor, and during the operation of the apparatus thecondenser and the space around the tubes d and the connecting-pipescontain only the chloride of ethyl and its vapors. The petcock k is nextclosed and the valve kis opened. The exhaust-pipe of the compressorexhausts the gas from the cylinderA, and the compressingpump compressesit and forces it into the condenser, where it is cooled and reduced tothe liquid state, ready to be returned to the cylinder A, and therecaused to expand again by the agency of the partial vacuum, which isretained therein by the exhaust of the comprcssor. From the condenserthe liquefied chloride of ethyl passes through the pipes on and 6 intothe cylinders A, where (the cylinders containing a partial vacuum) itexpands into a gas around the tubes at, thereby correspondingly reducingits temperature, so as to extract the heat from the pipes d and the airpassing through them. In the expanded state the chloride of ethyl isdrawn by the exhaust of the compressor through the pipes f j back to thecylinder B, where it is compressed, and then goes through the sameoperation over again. While the treatment of the chloride of ethyl isprogressing, as above described, the pressureblower draws air out of thechillroom and forces it under a slight pressure through the pipes r andi into the inclosed spaces surrounding the cylinders A. Thence the air,still under a slight pressure, passes through the pipes 1) within thespace between the caps a and the perforated plates 0, and thence throughthe tubes (1 and intb the space between the cap a and perforated plate0. From this space the air is conducted through the pipes b and 15 backto the chill-room, into which it is distributed by the pipes at from theopenings 0. y In its turn this air is again drawn into the pipe q andthe same operation upon it is repeated.

In making the excursion above described the air is not finally cooledtill it reaches the tubes cl,- but as it passes through the tubes cl thedifference in area between the pipes b and 1), already mentioned,assists the pressure-blower in keeping the air under a slight pressure,which aids in bringing it into'intimate contact with the interior of thetubes d, and its heat is taken up by the pipes and given by them to thechloride of ethyl surrounding them, which carries it to the condenserand leaves it there, preparatory to returning to take away the heat ofany other air which may be passing through the tubes, when it returns tothe cylinders A. Not only is the air in this manner deprived of its heatas it passes through the tubes, but by reason of its loss of heat italso loses its capacity to hold moisture, and its moisture is thereforedeposited on the interior of the tubes in the form of ice or snow, theair in the chill-room being thus kept very dry. Still another impuritywhich the air leaves in the tubes in case the apparatus is applied torefrigerating fermenting-rooms is the carbonieacid gas resulting fromthe fermentation, which gas is very soluble in the moisture held by theair when it enters the tubes, but is very slightly soluble by the dryair as it leaves the tubes. fore dropped by the air and left in solutionin the snow or ice deposited in the tubes. So marked is this result thatfermenting-rooms, which,when refrigerated as heretofore, habituallycontained so much carbonic-acid gas that The gas is there-' IIO a lampcould starcely be burned in them, when refrigerated by my apparatus, arekept practically free from any carbonic-acid gas whatsoever. Thepresence of the gas in the snow or ice deposited in the tubes is shownby the acid reaction it has upon'litmuspaper. The moisture andimpurities taken up by the air in the chill-room being thus deposited011 the interior of the tubes (1, those tubes, after long-continuedoperation,require to be cleaned out. To do this to the tubes in anycylinder, I close the valves in the connecting-pipes of that cylinder,and at'the same time open the valves in the cylinder which waspreviously 1 idle. Of the cylinder thus cut off I open the caps a a byswinging the two halves of each cap back on their hinges. The tubeswithin the cylinder are thus exposed at both ends, and to clean them outI cause water of the ordinary temperature, or steam or othercomparatively-temperate fluid, to flow through them. This water thawsthe snow and ice deposited in the tubes and washes them all out clean.The caps of the cylinder are then closed, and the cylinder is ready tobe put into operation again whenever needed. In this manner I amenabled,without interfering with the operation of the apparatus, to keepit free from obstructions.

In order to produce a temperature below the boiling-point of therefrigerating-fluid, (which for chloride of ethyl is 52?.) it isnecessary that the capacity of the compressingpump and the relativeareas of the pipes leading from the compressor to and from therefrigerator should be so regulated that in operation a partial vacuumis continually preserved around the tubes cl within the cylinders A. Theextent of vacuum required will depend upon the lowness of thetemperature desired for the air.

I In practice I have found that when the air being delivered into thechill-room showed a temperature of 40 Fahrenheit a vacuunr gageconnected with the interior of the cylinder A registered about fifteeninches, and when the air being delivered to the chill-room was at about28 Fahrenheit the vacuum-gage stood at twenty inches, though thevacuumgage in these instances would have registered less if the air fromthe chill-room had been passed more frequently through the pipes d thanit was in fact, the air in the chill-room in the examples referred tobeing passed through the tubes (2 once everyhour. In order to providefor producing this partial vacuum within the cylinders A, I place in thebranch pipes leading from the pipe 6 to each refrigerator check-valves 6near the point where each branch pipe empties into its refrigerator, bypartially closing which I am enabled to so impede the passage of thefluid from the condenser to the refrigerator as to prevent its beingsupplied to the refrigerator sufficiently fast to fully supply the placeof the gas which is exhausted from the refrigerator by thecompressing-pump. Thus the extent of vacuum quently the temperaturecommunicated to the air passing through the tubes (1, may be regulatedat will by simply varying the position of the check-valve e, and thefluid does not begin to vaporize practically until after it has passedthe valve 0.

I have described the apparatus which I prefer to use in practicing myinvention; but it will be apparent that the apparatus .may be varied inmany features without departing from the scope of my invention.

So far as I know, previous to my invention no apparatus was knownpractically adapted for the application of chloride of ethyl as arefrigerating agent to the refrigeration of air, and I believe myself tobe the first one to refrigerate air by means of chloride of ethyl. Ifurthermore believe that' my apparatus contains certain novel featureswhich might be used to advantage in refrigerating with other agents thanchloride of ethyl.

Some of the advantages of my method are the following: Very littlepressure is required to compress the chloride of ethyl, thus requiringlittle power or strength of machinery, and producing little wear ofmachinery and little liability of breakage, leakage, and loss of thefluid. The chloride of ethyl is neutral, and attacks no metal; thereforeany metal can be used in the construction of the machine, and I amenabled to use copper for the tubes (2, (one of the best conductors ofheat,) while with some other fluids only iron can be used, which is oneof the poorest conductors, and does not make tight joints, as doescopper. Chloride of -ethyl is not noxious to the smell or injurious tothe health.

In my machine all of the parts of the apparatus traversed by therefrigerating-fluid may be in the machine-room, readily accessible tothe engineer. The tubes cl can be readily cleaned of any moisture frozenin them which tends to impair their conductivity or obstruct them.Access to the apparatus does not require the chill-room to be opened.The atmosphere of the chill-room is deprived of can bonic-acid gas andother impurities. Chloride of ethyl, when expanded so as to producecold, deposits crystals on any substance with which it may be incontact, which crystals accumulate so as to have the appearance of frostor snow. It also expands slowly when volatilized.

I am aware that attempts have heretofore been made to use chloride ofethyl for freezing liquids; but I do not know of any attempts prior tomyinventions in this direction which were practically successful.

One of the principal reasons why the apparatuses before known could notbe used with practical advantage with chloride of ethyl has been becausethe expansion of the chloride of ethyl took place in a passage ofrestricted sectional areain fact of a sectional area not greater thanthe supply pipe for the comproduced within the refrigerator, and conse-ICO pressed fluid. When expanded in such a passage, the tendency of thegas to form the crystals referred to andthe slowness of its expanwhenthe gas first begins to expand and pre- L vents further circulation, andthe slowness of the expansion of the gas prevents its being diffusedquickly throughout the remoteend of the expansion passage, and therebyprevents a uniform distribution of cold. In my method and apparatusprovision is made for introducing the fluid to be expanded within achamber of large sectional area in comparison with the sectional area ofthe supply-pipe, so that whatever crystals may be created within thechamber and deposited therein will occupy so small a space in comparisonwith the sectional area of the expanding passage or chamber as not tomaterially obstruct the passage of the expanded gas through the same.These crystals spontaneously volatilize when exposed to a temperaturehigher than the temperature at which they are formed, so that wheneverthe apparatus is stopped any accumulation of them which has been formedin the expansion-chamber will spontaneously disappear. By having theexpansion-chamber of large sectional area, my method is also adapted forthe slowness with which the fluid expands, and the gas is diffusedthroughout all portions of the chamber with sufficient rapidity.

It will be noticed that the bottom of the condenser is above the levelof the bottom of the refrigerator, so that in the relationship of theapparatus shown in the drawings the chloride of ethyl would existthroughout the greater part of the condenser in a gaseous condition,which will be converted into a liquid as it becomes cool, and willcollect in a liquid form to a comparatively small extent at the bottomof the condenser. This liquid, running through the connecting-pipe intothe refrigerator, will collect therein to a considerable depth, where,as it gradually absorbs heat from the air-tubes, it will be convertedinto a gas, which accumulates in the upper portion of the refrigerator.This gas apparently is generated in various portions of the liquid,where it comes in contact with the heating surfaces, and as it bubblesup through the liquid chloride of ethyl from the points at which it isgenerated it readily escapes from the large area of exposed surface, andthe gas produces a boiling effect in the refrigerator.

The apparatus I have described may be 10-- cated outside the chill-roomwith pipes connecting therewith, or it may be located within thechill-room, or partly inside and partly outside.

I have made an application of even date herewith for certain features ofthe above invention, and I therefore do not claim those features in thisapplication.

' I am aware of the patent granted to Charles Tellier, dated'January 5,1869, and numbered 85,719, and do not make claim to anything thereindescribed. That patent states that it is necessary in cooling air by theTellier method not to allow the air to be cooled below the freezingpointin the apparatus. This would not reduce the temperature of a chill-roomsufficiently for practical purposes, and together with other featuresrenders the Tellier method incapable of accomplishing the results forwhich mine-is adapted.

I am also aware of the patent to LG. \Volf, dated March 9, 1879, No.213,487, and make no claim to anything shown therein.

I claim- 1. The method or process, substantially as described, ofcooling air, which consists in compressing chloride of ethyl, cooling 1twhen compressed, volatilizing it in a chamber of sufficient area whereinto deposit its crystals without obstructing the passage of gas, andcausing the volatilized gas to circulate in contact with a conductor ofheat, on the opposite side of which conductor the air circulates,whereby the heat communicated by the air to said conductor is carriedoff by the gas.

2. The method or process, substantially as described, of cooling air,which consists of compressing chloride of ethyl, cooling it whencompressed, volatilizing it in a chamber of sufficient area wherein todeposit its crystals without obstructing the passage of gas, and causingthe air to circulate through a passage adjoining the passage throughwhich said volatilized chloride of ethyl is passed.

3. The improvement in the art of cooling air by the agency of a volatilefluid which is compressed and cooled and volatilized in such manner asto absorb the heat from the air, which improvement consists involatilizing chloride of ethyl within a closed chamber of sufficientsectional area to prevent the passage of volatilized fluid through thesame being obstructed by the crystals which may be deposited upon thewall of the chamber by the fluid undergoing volatilization.

4. The process of refrigerating by means of chloride of ethyl, whichconsists of compressing and condensing it and then allowing it tovaporize within a receptacle, constructed substantially as described,whereby sufficient area of surface of the liquefied fluid is exposed topermit the gas which is formed therein to es cape freely into the upperportion of the receptacle.

5. The improvement in the art of cooling air by the agency of a volatilefluid, which consists in subjecting the air as it passes through tubestothe cooling action of the fluid volatilized within a vesselsurrounding said tubes by the agency of a partial vacuum, substantiallyas described.

6. Ina refrigerator, the combination of the cylinderA, the tubes (1,opening into air-spaces at each end, inlet and outlet air-passages Zan'db, connecting said air-spaces with the chillroom, thepressure-blower connected with the pipe I), for driving the air throughthe tubes (1 under pressure, and suitable connections for conducting thevolatile fluid to and from the cylinder A, substantially as described.

7. In combination with the pressure-blower, the vessel A,having theair-tubes d and inlet and outlet air-passages to and from said tubes,the area of the outlet-passage being less than the area of theinlet-passage, substantially as and for the purpose described.

8. In combination, a refrigerator provided with tubes for the passageofair, and a closed 5 chamber surrounding said tubes, constructed tohold a volatile fluid, inlet and outlet pipes connecting said air-tubeswith the chill-room, pipes connecting the closed chamber with acompressor constructed to draw the volatilized fluid from said closedchamber, and a condenser for cooling the same when compressed,substantially as described.

9. The process of keeping the air of a chillroom at a temperature below50 Fahrenheit for preserving purposes, which consists in passing thesame through tubes adjoining a chamber connected with a gas compressorand condenser, and preserving in said chamber a partial vacuum, thuscausing a volatile fluid to volatilize therein at a low temperature.

10. In combination, the tubes for the passage of the airbeing cooled,the adjoining volatilizing-chamber, the fluid-compressor having exhaustand pressure passages connecting the compressor with thevolatilizing-chamber, said passages being provided with means for makingthe pressure-passage of less area than the exhaust-passage, whereby thecompressor may produce a partial vacuum within the volatilizing-chamberfor volatilizing the fluid.

11. The chill-room, the air-cooling tubes connected by inlet and outletairpassages with the chill-room, the air-forcing apparatus for forcingthe air over and over again through the air-cooling tubes, thevolatilizing-ehamber surrounding the air-cooling tubes, and connectedwith the exhaust and pressure passages of the compressor, and means forregulating the relative areas of said passages, all combinedsubstantially as described.

GASSIUS CLAY PALMER.

\Vitnesses:

DANIEL H. DRISCOLL, XV. F. Hareoon.

